MVC3 驗證碼

生成驗證碼：

//// <summary>
        /// 生成驗證碼
        /// </summary>
        /// <param name="length">指定驗證碼的長度</param>
        /// <returns></returns>
        public string CreateValidateCode(int length)
        {
            int[] randMembers = new int[length];
            int[] validateNums = new int[length];
            string validateNumberStr = "";
            //生成起始序列值
            int seekSeek = unchecked((int)DateTime.Now.Ticks);
            Random seekRand = new Random(seekSeek);
            int beginSeek = (int)seekRand.Next(0, Int32.MaxValue - length * 10000);
            int[] seeks = new int[length];
            for (int i = 0; i < length; i++)
            {
                beginSeek += 10000;
                seeks[i] = beginSeek;
            }
            //生成隨機數字
            for (int i = 0; i < length; i++)
            {
                Random rand = new Random(seeks[i]);
                int pownum = 1 * (int)Math.Pow(10, length);
                randMembers[i] = rand.Next(pownum, Int32.MaxValue);
            }
            //抽取隨機數字
            for (int i = 0; i < length; i++)
            {
                string numStr = randMembers[i].ToString();
                int numLength = numStr.Length;
                Random rand = new Random();
                int numPosition = rand.Next(0, numLength - 1);
                validateNums[i] = Int32.Parse(numStr.Substring(numPosition, 1));
            }
            //生成驗證碼
            for (int i = 0; i < length; i++)
            {
                validateNumberStr += validateNums[i].ToString();
            }
            return validateNumberStr;
        }

 

/// <summary>
/// 創建驗證碼的圖片
/// </summary>
/// <param name="containsPage">要輸出到的page對象</param>
/// <param name="validateNum">驗證碼</param>
public byte[] CreateValidateGraphic(string validateCode)
{
    Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 22);
    Graphics g = Graphics.FromImage(image);
    try
    {
        //生成隨機生成器
        Random random = new Random();
        //清空圖片背景色
        g.Clear(Color.White);
        //畫圖片的干擾線
        for (int i = 0; i < 25; i++)
        {
            int x1 = random.Next(image.Width);
            int x2 = random.Next(image.Width);
            int y1 = random.Next(image.Height);
            int y2 = random.Next(image.Height);
            g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
        }
        Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
        LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),
         Color.Blue, Color.DarkRed, 1.2f, true);
        g.DrawString(validateCode, font, brush, 3, 2);
        //畫圖片的前景干擾點
        for (int i = 0; i < 100; i++)
        {
            int x = random.Next(image.Width);
            int y = random.Next(image.Height);
            image.SetPixel(x, y, Color.FromArgb(random.Next()));
        }
        //畫圖片的邊框線
        g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
        //保存圖片數據
        MemoryStream stream = new MemoryStream();
        image.Save(stream, ImageFormat.Jpeg);
        //輸出圖片流
        return stream.ToArray();
    }
    finally
    {
        g.Dispose();
        image.Dispose();
    }
}

控制層：

View Code

public ActionResult GetValidateCode()    
    {    
        ValidateCode vCode = new ValidateCode();    
        string code = vCode.CreateValidateCode(5);    
        Session["ValidateCode"] = code;    
        byte[] bytes = vCode.CreateValidateGraphic(code);    
        return File(bytes, @"image/jpeg");    
    }  

視圖層：

View Code

<p>  
<img id="valiCode" style="cursor: pointer;" src="/Home/GetValidateCode" alt="驗證碼" />  
</p>  
  
<script>  
    $(function () {    
        $("#valiCode").bind("click", function () {    
            this.src = "/Home/GetValidateCode?time=" + (new Date()).getTime();    
        });    
    });</script>  

 

這里還有一個封裝好的MVC驗證碼組件,也很好用.

 http://www.webdiyer.com/mvccaptcha/